The molar conductivities at infinite dilution for the strong electrolytes $\mathrm{NH}_4 \mathrm{Cl}

Question

The molar conductivities at infinite dilution for the strong electrolytes $\mathrm{NH}_4 \mathrm{Cl}$, NaOH and NaCl are respectively $149.7 \Omega^{-1} \mathrm{~cm}^2 \mathrm{~mol}^{-1}, 248.1 \Omega^{-1} \mathrm{~cm}^2 \mathrm{~mol}^{-1}$ and $126.5 \Omega^{-1} \mathrm{~cm}^2 \mathrm{~mol}^{-1}$. The molar conductivity of $\mathrm{NH}_4 \mathrm{OH}$ at infinite dilution is

Professor PC Thomas Classes · Answer

Kohlrausch's law: $\Lambda^\circ(NH_4OH) = \Lambda^\circ(NH_4Cl) + \Lambda^\circ(NaOH) - \Lambda^\circ(NaCl) = 149.7 + 248.1 - 126.5 = 271.3$.